Unit 4 Flashcards
(59 cards)
what percent of Canada’s land is covered by forests?
42%
what two countries have more forest land than Canada?
Russia and Brazil
what trees make up Canada’s forests?
63% Coniferous trees (trees with needles)
22% Deciduous (trees with leaves)
15% mixed
Commercial Forest
part of the forest that 1) has large trees and 2) is close to the market
Non-Commercial Forest
part of the forest where: 1) trees are too small to harvest and 2) trees are too far from the market to transport
Economic Impact of Forests
- 1 out of 25 Canadian jobs are connected to the forest industry
- $300 billion a year industry (15 years ago)
- $80 billion dollars or 1/3 of those products are exported
what are the 3 ways to harvest trees?
1) Clear Cutting
–> all the trees in an area are cut
2) Shelter Wood Logging
–> 70% of the trees are cut
- leaves small patches of old growth to provide seeds
3) Selective Cutting
–> only trees of a certain type/size/quality are cut
Harvesting a Tree
- a harvester is used to clean trees - it is similar to a chainsaw
- it is attached to the hydraulic arm
- the hydraulic arm cuts the branches off the tree
Importance of Canada’s Forests
1) economic value
2) prevents flooding by holding water in the soil
3) provide habitats for wildlife
4) recreation / tourism
what is a mineral?
a mineral can be described as a naturally occurring, pure, non-living substance found in the rocks of the earth
examples of metallic minerals
cobalt, iron, uranium, zinc
examples of fossil fuels
coal, natural gas, oil
examples of industrial minerals
asbestos, gravel, gypsum, salt
what is a mineral reserve?
mineral deposits that are economical to mine are called mineral reserves (based off of the size and value of the mineral)
what steps are used by mining companies to discover and develop an ore body?
- ore bodies containing nickel, iron, and copper produce a powerful magnetic field so they can be detected using a magnetometer, an instrument towed by an airplane that shows approximate size and shape of an ore body
- satellite images and aerial photos tell geologists a lot about an area’s geologic structure
- all information is collected, analyzed, and presented using a GIS (geographic information system)
- much of the data that is needed can only be collected by going into the bush or tundra
> variety of techniques to collect data - collect rock samples for analysis in the field and in the lab
> test soil in river beds for chemicals that could have eroded from nearby ore bodies
> some minerals are radio active so they can be detected using a Geiger Counter - if the findings up until this point look promising, the next step would be to drill into the earth to get samples of the ore body itself
- then they decide whether or not the mining company will develop the mine
Open Pit Mining
mining used to extract minerals near the surface with the potential to be deeper
- soil/land above area is removed
- explosives are put into drilled holes 10-15 meters apart which blasts apart the rocks
- large trucks are loaded with the ore using large shovels
- the ore is taken to storage sites near the mill
Underground Mining
used to extract mineral ores located deep in the earth
- miners use a cage, or elevator, to go from the head-frame to the desired depth
- explosives fill drilled holes in the rock face of the stope
- an electric charge sets off the explosive, blasting the rock apart
- miners test the walls and ceiling after the blast and rock bolts and timber supports are added to prop up the weaker areas
- front-end loaders/small trains carry muck (blasted rock) to a central underground location and the muck is dropped down an ore pass to the crusher
- after the muck is crushed, it is loaded onto a skip, or hoist, which lifts the ore to the surface
- ore is then taken to a storage site near the mill
milling (takes place at the mill)
the mill starts the process of purifying the mineral by separating it from waste rock - this process makes the metal concentrated but far from pure
how are waste materials (tailings) disposed of?
tailing are dumped into tailing ponds within dikes which are designed to prevent the mine waste from seeping into the nearby lakes and rivers. it is then treated with fertilizers and other chemicals to allow trees and grasses to grow.
smelting (takes place at the furnace)
the ore concentrate and a substance called flux are melted together in a furnace. the flux joins with waste rock to form slag which is lighter than the liquid metal so it rises to the top then the almost pure metal is poured into molds
what provinces are most metallic minerals found in?
Ontario, Quebec, BC
what provinces are fossil fuels most found in?
Alberta, BC, Saskatchewan
what provinces are industrial minerals most found in?
Quebec, Ontario, Saskatchewan
what are Canada’s conventional sources of energy?
1) flowing water
2) fossil fuels (coal, natural gas, oil, uranium)
